Graph  Unit 
                            GraphResult Constants 

      PURPOSE:  Constant declarations used for Graphic errors

      REMARKS:  Internal errors in the Graph unit are reported through
                GraphResult.  The value returned reflects the status if the
                last graphics operation.  The following error return codes
                are predefined as constants in the Graph unit:

                      Const
                         grOK                  =   0;
                         grNoInitGraph         =  -1;
                         grNotDetected         =  -2;
                         grFileNotFound        =  -3;
                         grInvalidDriver       =  -4;
                         grNoLoadMem           =  -5;
                         grNoScanMem           =  -6;
                         grNoFloodMem          =  -7;
                         grFontNotFound        =  -8;
                         grNoFontMem           =  -9;
                         grInvalidMode         = -10;
                         grError               = -11;
                         grIOerror             = -12;
                         grInvalidFont         = -13;
                         grInvalidFontNum      = -14;
                         grInvalidDeviceNum    = -15;

                NOTE:  GraphResult is reset to 0 after it is called.